20445149 has 2 divisors, whose sum is σ = 20445150. Its totient is φ = 20445148.

The previous prime is 20445143. The next prime is 20445179. The reversal of 20445149 is 94154402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19201924 + 1243225 = 4382^2 + 1115^2 .

It is a cyclic number.

It is not a de Polignac number, because 20445149 - 2¹² = 20441053 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20445143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10222574 + 10222575.

It is an arithmetic number, because the mean of its divisors is an integer number (10222575).

Almost surely, 2^20445149 is an apocalyptic number.

It is an amenable number.

20445149 is a deficient number, since it is larger than the sum of its proper divisors (1).

20445149 is an equidigital number, since it uses as much as digits as its factorization.

20445149 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 20445149 is about 4521.6312321993. The cubic root of 20445149 is about 273.4408696771.

The spelling of 20445149 in words is "twenty million, four hundred forty-five thousand, one hundred forty-nine".